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The estradiol/testosterone ratio puts the hormone estradiol next to the hormone testosterone. In men, too much oestrogen can point to breast growth or fertility problems. In women, too much testosterone can point to a condition of the ovaries.[1, 2]
On this page, you can read what the oestradiol/testosterone ratio is, what the guidelines say about a value that is too low or too high, what affects your value and which other values are best looked at alongside it.
Also known as: oestradiol-testosterone ratio, E/T ratio. At the lab: not applicable.
Estradiol is the main oestrogen in women of childbearing age who are not pregnant. It is made mainly in the ovaries. Men make small amounts of it in the testicles.[1]
Testosterone is often called a male hormone, but women have it too, in smaller amounts. In everyone, it helps with sex drive and with the growth of muscles and bones.[2]
The ratio puts those two hormones side by side. It shows how much estradiol there is compared with testosterone.
Oestrogens do more than regulate reproduction. In men and women, they help with healthy cholesterol and blood sugar levels, strong bones and muscles, and brain functions such as being able to concentrate.[1]
In men, testosterone also plays a part in body hair, sperm production and the making of new red blood cells.[2]
An oestrogen value that stays too high or too low for a long time can point to a problem. A testosterone test on its own never diagnoses a condition. An abnormal result also does not always mean you need care.[1, 2]
| Level, as the source describes it | What it can point to | Who it is for |
|---|---|---|
| Oestrogen high[1, 2] | Often a sign of a condition, such as fertility problems | Men |
| Oestrogen persistently too high or too low[1, 2] | A condition of the ovaries, the thyroid or the pituitary gland, or early or late puberty | Women |
| Testosterone low[1, 2] | Problems with the testicles, a condition of the pituitary gland, or a long-term liver or kidney disease | Men |
| Testosterone high[1, 2] | Use of steroids, or a condition of the adrenal glands or the testicles | Men |
| Testosterone extremely low[1, 2] | A condition of the adrenal glands, the pituitary gland or the ovaries; a low value in itself is normal in women | Women |
| Testosterone high[1, 2] | A condition of the ovaries, the adrenal glands or the pituitary gland | Women |
Source: MedlinePlus (U.S. National Library of Medicine), on oestrogen and testosterone separately. The source gives no reference limits for the ratio itself.[1, 2]
A high ratio means a lot of estradiol compared with testosterone. In men, too much oestrogen can point to breast growth, late puberty, fertility problems or trouble getting or keeping an erection. In men, low testosterone can go together with less interest in sex, breast growth and loss of muscle mass.[1, 2]
A low ratio means a lot of testosterone compared with estradiol. In women, high testosterone can point to a condition of the ovaries, the adrenal glands or the pituitary gland. Symptoms that may go with it include extra hair growth on the body or face, acne and irregular or missed periods.[2]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
In men, oestrogen changes little over the course of life. In women, it changes a lot and rises during puberty. Testosterone normally falls with age.[1, 2]
Blood for testosterone is usually taken in the morning, between 7 and 10 am. Testosterone is usually at its highest during those hours.[2]
Some medicines can affect your values, such as the contraceptive pill and hormone therapy during the menopause. Tell your doctor everything you take. Never stop a medicine on your own, only when your doctor tells you to.[1, 2]
The estradiol/testosterone ratio is included in BioProfile 121 and 150.[3]
The BioProfile editorial team wrote this page on 7 November 2026 from the sources below, which we read on 7 November 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; once checked, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss an abnormal value with your GP.
